The field of the invention generally relates to draw stops attached directly or indirectly to a limb, cam, wheel, pulley or module of a compound bow. US patent classification F4165/1403 details of bows, and F4165/105 Cams or pullies for compound bows.
Draw stops are a common device used to limit the draw length, let-off, and valley, herein referred to as draw length, of a compound bow. Some cams, pullies, wheels or modules, herein referred to as cams, have a series of holes in it to mount a draw stop. The stop may hit a cable, string, limb, or other part of the bow, herein referred to as abutment surface, when drawn back resulting in the cam stopping also stopping the ability to draw the bowstring. The holes in the cam generally coordinate with specific lengths typically in one half inch increments. Mounting holes may also be in a module or other bracket attached to the cam. The draw stops are typically cylindrical in shape with the mounting axis coincident with the functional surface of the stop's axis. This configuration typically limits the draw lengths to one half inch increments.
There is a desire among archers to fine tune draw length closer than one half inch increments. There are several ways currently of doing this with the draw stops. The diameter of the cylindrical surface of the stop can be increased or decreased. This would require many different stops to cover the range of draw length.
Another way to limit is to adjust the abutment surface by applying material to it. This is not easily done and lacks consistency.
Another method is to use a stop with flats that are different lengths from the axis of the stop or a simple eccentric. The stop can be oriented differently to the abutment surface stopping the cam rotation at different lengths. This method requires the stop surface to be precisely aligned with the abutment surface, if it is not the resulting force will not be applied radially to the axis of the stop and it will result loosening or tightening the stop. Another problem from incorrect alignment is the length will not be consistent from one cam to another. One solution used for this problem is to use an orientation pin or orientation lug and pocket combination on the stop and cam.
The attempted solutions lack simplicity and versatility. They will either require many stops, precise alignment, or additional costly machining to the cam and stop to be versatile.